Process and apparatus for line production of plant growth medium pots or bags

ABSTRACT

A process for line production of plant growth medium pots or bags with a closed bottom end includes the steps of: i) continuously folding the free end of a continuous length of water and air permeable sheet material into a sheet material tube around and beyond a free end of a growth medium feeding tube; ii) forming a first sealing in the sheet material tube; iii) filling the sheet material tube with a measured amount of growth medium; iv) forming a second sealing in the sheet material tube; v) separating the part of the sheet material tube positioned downstream from the second sealing to form a first plant growth medium pot or bag with a closed end, repeating as needed to form a plurality of plant growth medium pots or bags.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the production of growth medium pots orbags.

BACKGROUND OF THE INVENTION

Today, most of the greenhouses and nurseries applying hydroponic growthof herbs utilize injection moulded plastic pots. This is veryproblematic, as there is a dramatic increase of plastic waste in generalin the world. Furthermore, when the herbs are harvested, the plasticpots are seldom separated from the root and growth medium, and bothparts are therefore not recycled.

Another present issue is with the downsides of polythene seedling bagsfor trees and bushes in nurseries. In many countries, aftertransplanting, the bags are discarded, burned or buried on agriculturalland. Bags discarded on farms can enter waterways and cause blockage andmay also suffocate aquatic animals. Domestic and wild animals sometimesswallow them, with disastrous effects. The bags also serve as breedingsites for mosquitoes and other disease vectors. Burying the polythenebags in the soil interferes with proper water percolation and aerationof the soil and burning them produces noxious smoke. Hence, there is aneed to find an alternative solution.

WO2013174386 discloses a method of manufacturing a plant receptacle,wherein the following steps are performed: a) a PLA thread isco-extruded with a flexible aliphatic polyester, said flexible aliphaticpolyester comprising 10 wt % to 30 wt % bamboo material, such that theflexible aliphatic polyester covers the PLA thread, thereby creating aweldable biodegradable thread; b) using said weldable biodegradablethread in a woven or non-woven process, making a permeable sheetmaterial; c) continuously forming said sheet material into a continuousreceptacle, by bringing the side edges of said sheet material intocontact and welding said side edges together; d) cutting said continuousreceptacle in predetermined lengths thereby creating separate plantreceptacles. Such plant receptacles are not suitable for hydroponicsystems as the growth medium will fall out of the pot or bag and intothe pot or bag trays of the hydroponic system, thereby obstructingfilters and pumps.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an alternativegrowth medium pot or bag to replace the environmentally unfriendlyinjection moulded plastic pots or bags. Additionally, it is an object toprovide a growth medium pot or bag suitable for hydroponic systems.Furthermore, it is an object to provide machinery for their production.

A first aspect relates to a process for line production of plant growthmedium pots or bags with a closed bottom end comprising the steps of:

i) continuously folding the free end of a continuous length of water andair permeable sheet material, preferably supplied on a reel, into a(growing) sheet material tube around and beyond a free end of a growthmedium feeding tube;

ii) forming a first sealing in the sheet material tube by engaging andflattening the opposed walls of the sheet material tube at a positionbeyond the free end of the growth medium feeding tube;

iii) through the free end of the growth medium feeding tube, filling thesheet material tube with a measured amount (a dosage) of growth medium;

iv) forming a second sealing in the sheet material tube by engaging andflattening the opposed walls of the sheet material tube at a positionabove the position of the growth medium;

v) separating the part of the sheet material tube positioned downstreamfrom the second sealing to form a first plant growth medium pot or bagwith a closed end; and

optionally

vi) repeating the steps i), and iii)-v) several times to form aplurality of plant growth medium pots or bags with a closed end.

The step ii) is an initiation step that is present to make a closed endin the sheet material tube. The tube will subsequently be closed due tothe formation of the second sealing.

By using a water permeable sheet material, preferably biodegradable,woven or nonwoven, there is no need for the environmentally unfriendlyinjection moulded plastic pots or bags. Rather, the water permeablesheet material may be recycled together with the plant roots and growthmedium in a composting facility. The sheet material must be waterpermeable in order for the produced plant pot or bag to be able toabsorb water and dissolved nutrients. The growth medium pot or bag has aclosed bottom end to avoid that growth medium will fall out of the potor bag and into the pot or bag trays of the hydroponic system, therebyobstructing filters and pumps.

The term “biodegradable” as used herein describes the chemicaldissolution of materials by bacteria or other biological means.

As used herein, the term “nonwoven sheet material” means a sheetmaterial that has a structure of individual fibers or threads, which areinterlaid, but not in an identifiable repeating manner. Nonwoven sheetmaterials may be formed by a variety of processes such as, for example,meltblowing processes, spunbonding processes, coforming processes,airlaying processes, wetlaying processes, and hydroentangling.

The fibers used for the water permeable sheet material are preferablybiodegradable, which can be natural or synthetic fibers, e.g. cellulosicfibers, protein fibers or synthetic polymer fibers. Natural fibers cancomprise pulped or shredded cellulose fibers, such as wood pulp,shredded wood, shredded paper (tissue, newsprint and the like), straw,cotton fiber, composted vegetation, fibrous sphagnum moss, peat moss,shredded stalks including shredded corn stalks and shredded pine straw(including needles, twigs, cones and small branches). Shreddedvegetation is preferably dry before shredding. Protein fibers can e.g.be hair or gelatin. Biodegradable synthetic fibers can comprisereconstituted cellulose fibers, such as rayon fibers, vinyl polymerfibers, such as fibrous polyvinyl alcohol, poly lactic acid, andpolyamide fibers.

The term “cellulosic fibers” as used herein describes fibers made froman organic compound derived primarily from plants such as trees.

The term “wood pulp fibers” as used herein describes a type ofcellulosic fiber made from a lignocellulosic fibrous material preparedby chemically or mechanically separating cellulosic fiber from plantssuch as trees or cotton.

The term “regenerated/reconstituted cellulosic fibers” as used hereindescribes a type of cellulosic fiber made from wood pulp using a solventfiber spinning process. The process involves dissolving wood pulp in asolvent and spinning the resultant spinning solution into fibers.

In one or more embodiments, the biodegradable and water permeable sheetmaterial consist of spunlaced fibers without fiber binding materials.The term “spunlaced” as used herein refers to a structure of individualfibers or threads, which are physically entangled, without thermalbonding. Physical entanglement may be achieved using a waterentanglement process, or alternatively, a needling process or acombination of both processes. The spunlaced fibers provide the strengthto the water permeable sheet without the need for a binder, also, andvery importantly for the present use, when the water permeable sheet iswet.

In order for the water permeable sheet material to be sealable, at leastsome of the fibers should preferably be made from, or coated with, athermoplastic material. Alternatively, the water permeable sheetmaterial could be coated with a hotmelt composition. Another method forsealing the sheet material tube may be to emboss or sew the sheet partstogether.

In one or more embodiments, the water permeable sheet material is heatsealable.

In one or more embodiments, step i) comprises sealing the overlappingsheet side parts to one another.

In one or more embodiments, the water and air permeable sheet materialcomprises a) fibers coated with a thermoplastic material and/or b)fibers of a thermoplastic material; and wherein the sealings are made byheating.

In one or more embodiments, the step of continuously folding the freeend of a continuous length of water and air permeable sheet materialinto a sheet material tube comprises sealing the overlapping sheet sideparts to one another. Such a sealing is preferable a heat seal extendingalong the entire length of the sheet material tube. Such a seal may beprovided by applying heat to the overlapping sheet side parts thatoverlay the free end of the growth medium feeding tube.

The water permeable sheet material must obviously be advanced during thecontinuous process. Different means may be used, such as a pair of jawsconfigured to move in the water permeable sheet material advancementdirection during their engagement with the sheet material tube. In oneor more embodiments, the continuous length of water and air permeablesheet material is advanced by grabbing the first sealing in the sheetmaterial tube and pulling the first sealing further away from the freeend of the growth medium feeding tube. The advantage of grabbing thefirst sealing is to avoid that the sheet material brakes during thepulling operation. Subsequently to separating the first sealing (tobottom in the first plant growth medium pot or bag) from the advancinggrowth medium feeding tube, the air permeable sheet material is advancedby grabbing the second sealing in the sheet material tube and pullingthe second sealing further away from the free end of the growth mediumfeeding tube.

The pair of jaws may be welding jaws configured to make the sealings.

In one or more embodiments, the seals of the sheet material tube areair-cooled prior to the water permeable sheet material advancementoperation. This configuration allows for faster production, as thesealings are strengthened rapidly.

A second aspect relates to an apparatus for use in the process of thepresent invention, the apparatus comprising:

-   -   a storage container adapted for holding growth medium, and        comprising a growth medium feeding tube; wherein the storage        container is adapted for delivering dosages of growth medium        through its growth medium feeding tube;    -   means adapted for continuously folding the free end of a        continuous length of water and air permeable sheet material,        preferably supplied on a reel, into a sheet material tube around        the growth medium feeding tube;    -   a suction chamber adapted to be positioned around and beyond the        free end of the growth medium feeding tube, and adapted to be        in a) an open first configuration and b) in a closed second        configuration; wherein when in the closed second configuration        the suction chamber encloses the free end of the growth medium        feeding tube and the sheet material tube formed around it, and        engages and flattens the opposed walls of the sheet material        tube at a predefined distance downstream from the free end of        the growth medium feeding tube; and subsequently removes air out        of the chamber, such that a dosage of growth medium in the        storage container is transported through the growth medium        feeding tube and into the sheet material tube within said        suction chamber;    -   a first sealing means adapted for forming a sealing in the sheet        material tube by engaging and flattening the opposed walls of        the open end of the sheet material tube at a position downstream        to the suction chamber;    -   wherein the free end of the growth medium feeding tube is        configured with one or more perforations or slits extending        through its walls; and    -   cutting means adapted for separating a formed plant growth pot        or bag from the continuous length of water permeable sheet        material.

The cutting means may e.g. be a knife, a sharpened blade, or a laserbeam.

In one or more embodiments, the first sealing means is integrated intothe bottom part of the suction chamber.

In one or more embodiments, the sheet material tube is sealed along itslength, e.g. by a lap sealing. In one or more embodiments, the apparatusfurther comprises a second sealing means adapted for heat sealing theoverlapping sheet side parts of the sheet material tube to one another.In one or more embodiments, the apparatus further comprises a secondsealing means adapted for lap sealing the sheet material tube. Thesealing is preferably made on the tube part when it passes over thegrowth medium feeding tube. Thereby, a part of the free end of thegrowth medium feeding tube serves as a part of the sealing means. In oneor more embodiments, a part of the free end of the growth medium feedingtube comprises a protrusion adapted for receiving a welding jaw.

In one or more embodiments, the storage container comprises:

-   -   a storage compartment with an outlet in the bottom wall;    -   a stirrer configured to maintain the growth medium homogeneous        in the storage compartment; and    -   an open-ended dosing chamber configured to move between a first        position and a second position; wherein its first open end        connects to the outlet of the storage compartment in the first        position, and wherein its second open end connects to the inlet        of the growth medium feeding tube in the second position. When        the first open end disconnects from outlet of the storage        container, it removes a dosage of growth medium from the storage        container, through the open-ended dosing chamber, and into the        growth medium feeding tube.

The storage container with a dosing chamber is a new way of thinkingwithin the field of paper pots, where the growth medium is normallydelivered into a cylindrical paper tube as a continuous mass (see e.g.WO1992003914). Such a configuration is not possible, when producing aplant pot or bag according to the present invention. In order to providespace for making the sealings, the growth medium must be provided intothe cavity of the continuously formed sheet material tube. Therefore,the growth medium should be delivered in doses.

In one or more embodiments, the open-ended dosing chamber is configuredas a block with a channel extending therethrough, and wherein the firstopen end of the channel connects to the outlet of the storage containerin the first position, and wherein the second open end of the channelconnects to the inlet of the growth medium feeding tube in the secondposition. In one or more embodiments, the block is slidingly engagedwith the bottom wall of the of the storage container.

In one or more embodiments, the open-ended dosing chamber is slidinglyengaged with bottom wall of the of the storage container.

In one or more embodiments, the stirrer is configured to change rotationdirection each 2-10 dosing operations. This configuration is to avoiddemixing of the growth medium.

In one or more embodiments, the stirrer paddle blade/head is configuredas one or more cylindrical rods extending radially away from the stirrershaft. This configuration is to avoid demixing of the growth medium.

In one or more embodiments, the apparatus further comprises a pistonconfigured to move through the first and second open ends of theopen-ended dosing chamber when the open-ended dosing chamber is in thesecond position.

A third aspect relates to a growth medium pot or bag obtainable by theprocess according to the present invention.

A fourth aspect relates to a growth medium pot or bag with a closedbottom end and an open top end, the growth medium pot or bag comprisinga tubular sheet material surrounding a portion of growth medium; whereinthe tubular sheet material is made of a single sheet of water and airpermeable sheet material being sealed with two seals formed in saidsheet material; wherein the first seal is a lap seal joining the twosides of the sheet material to form a tube; and wherein the second sealis formed in one of the ends of the tubular sheet material by engagingand flattening the opposed walls of the sheet material tube.

In one or more embodiments, the second seal is a tap seal.

As used in the specification and the appended claims, the singular forms“a”, “an”, and “the” include plural referents unless the context clearlydictates otherwise. Ranges may be expressed herein as from “about” or“approximately” one particular value and/or to “about” or“approximately” another particular value. When such a range isexpressed, another embodiment includes from the one particular valueand/or to the other particular value. Similarly, when values areexpressed as approximations, by use of the antecedent “about”, it willbe understood that the particular value forms another embodiment.

It should be noted that embodiments and features described in thecontext of one of the aspects of the present invention also apply to theother aspects of the invention.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows an apparatus for use in the process in accordance withvarious embodiments of the invention;

FIG. 2 shows a part of the storage container in accordance with variousembodiments of the invention;

FIG. 3 shows an example of how to fold the sheet material into a tubularsheet material;

FIG. 4 shows the suction chamber relative to the free end of the growthmedium feeding tube in accordance with various embodiments of theinvention; and

FIG. 5 shows parts of the apparatus for sealing, pulling, and cutting ofthe tubular sheet material.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows an apparatus 100 for line production of plant growth mediumpots or bags.

The apparatus comprises a storage container 200 with a growth mediumfeeding tube 208 (partly shown), folding means 300, a suction chamber400 (shown in a closed position), and a first sealing means 500 (partly,only one of the two welding jaws may be seen).

The storage container 200 is here shown with two storage chambers, afirst storage chamber 202 adapted for holding a large amount of growthmedium, and a second storage chamber 204 for holding a relativelysmaller amount of growth medium. Growth medium is transported from thefirst storage chamber 202 to the second storage chamber 204 by aconveyor belt 206. In FIG. 2, the second storage chamber 204 is shownrelative to an open-ended dosing chamber 210. The open-ended dosingchamber 210 is configured to move between a first position and a secondposition with the aid of a pneumatic/hydraulic cylinder 212, asindicated by an arrow. A first open end 211 of the open-ended dosingchamber 210 connects to the outlet 205 of the second storage chamber 204in the first position, and wherein the second open end 213 (not shown,but indicated by an arrow) connects to the inlet of the growth mediumfeeding tube 208 in the second position (here shown in the secondposition), while the first open end 211 disconnects from outlet 205 ofthe second storage chamber 204, thereby removing a dosage of growthmedium from the second storage chamber 204, through the open-endeddosing chamber 210, and into the growth medium feeding tube 208. Thestorage container 200 further comprises a piston 220 configured to movethrough the first 211 and second 213 open ends of the open-ended dosingchamber 210 when the open-ended dosing chamber 210 is in the secondposition. This piston is not necessary when producing larger pots orbags. A stirrer paddle blade/head 230 is configured as two cylindricalrods extending radially away from the stirrer shaft. This configurationis to avoid demixing of the growth medium.

FIG. 3 shows an example of how to fold the sheet material into a tubularsheet material. The folding means 300 is adapted for continuouslyfolding the free end of a continuous length of water and air permeablesheet material 10 supplied on a reel 20, into a sheet material tube (notshown) around the growth medium feeding tube 208. The folding means 300is here shown comprising two ring- or tube-shaped units. The uppertube-shaped unit 310 is a guide means adapted for securing that one sideof the sheet material 10 is continuously positioned below the other sideof the sheet material 10 in order to position the sides relative to eachother for a lap seal to be formed. The lower ring-shaped unit 320 isadapted to form the sheet material tube. Both units are positionedaround the growth medium feeding tube 208 that thereby also aids in thefolding operation. The free end of the growth medium feeding tube 208 isconfigured with two slits 209 (only one is shown) extending through itswalls. The two slits secure that the part of the sheet material tubethat extends beyond/below the free end of the growth medium feeding tube208 will not collapse during the filling operation. Otherwise, thedosage of growth medium would not be able to be correctly positionedtherein.

FIG. 4 shows the suction chamber 400 relative to the free end of thegrowth medium feeding tube 208 in accordance with various embodiments ofthe invention. The suction chamber 400 is positioned around and beyondthe free end of the growth medium feeding tube 208, and adapted to be ina) an open first configuration (as shown) and b) in a closed secondconfiguration. In the closed second configuration, the suction chamber400 encloses the free end of the growth medium feeding tube 208, and thesheet material tube (not shown) formed around it. Furthermore, itengages and flattens the opposed walls of the water and air permeablesheet material tube at a predefined distance downstream from the freeend of the growth medium feeding tube 208; and subsequently removes airout of the chamber (e.g. by the aid of a pump as seen to the right sidein FIG. 1), such that a dosage of growth medium in the dosing chamber210 and/or in the growth medium feeding tube 208, is transported throughthe growth medium feeding tube 208 and into the sheet material tubewithin said suction chamber 400. The free end of the growth mediumfeeding tube 208 is configured with multiple perforations 209 (three areshown) extending through its walls. The perforations secure that thepart of the sheet material tube that extends beyond/below the free endof the growth medium feeding tube 208 will not collapse during thefilling operation. Otherwise, the dosage of growth medium would not beable to be correctly positioned therein. A second sealing means isconfigured for sealing the sheet material tube along its length, here alap sealing. The lap sealing is made on the sheet material tube when itpasses over the growth medium feeding tube. The second sealing meanscomprises a welding jaw 610, and wherein a part of the free end of thegrowth medium feeding tube comprises a protrusion 620 adapted forreceiving said welding jaw 610. Thereby, a part of the free end of thegrowth medium feeding tube 208 serves as a part of the second sealingmeans.

FIG. 5 shows parts of the apparatus for sealing, pulling, and cutting ofthe tubular sheet material. The first sealing means 500 (here configuredas two welding jaws) is adapted for forming a sealing in the sheetmaterial tube 12 by engaging and flattening the opposed walls of theopen end of the sheet material tube 12 at a position downstream to thesuction chamber (not shown). The sealing is performed while the suctionchamber is in the closed second configuration. When the two welding jawsretract, the suction chamber moves to its open first configuration, andthe continuous length of water and air permeable sheet material isadvanced by grabbing and pulling means 800 configured for grabbing theformed sealing in the sheet material tube and pulling the sealingfurther away from the free end of the growth medium feeding tube (notshown). The advantage of grabbing the sealing is to avoid that the sheetmaterial brakes during the pulling operation. The grabbing and pullingmeans 800 is here shown comprising to jaws 810, 820 adapted for grappingthe sealing. The jaws 810, 820 are shown grabbing the sealing, while thetwo welding jaws are in a retracted position.

A cutting means 700 is also shown in a retracted position. The cuttingmeans is adapted for separating the formed plant growth pot or bag 30from the continuous length of water permeable sheet material. Thecutting operation is performed subsequently to the pulling operation.

An example of a growth medium pot or bag 30 produced by the process ofthe present invention is also shown in FIG. 5. Typical pots or bagsprepared by the present invention have a diameter of 20-200 mm, and aheight of 20-500 mm. The growth medium pot or bag 30 has a closed bottomend and an open top end and comprises a tubular sheet material 32surrounding a portion of growth medium 34. The tubular sheet material ismade of a single sheet of water and air permeable sheet material beingsealed with two seals formed in said sheet material. The first seal is alap seal 36 joining the two sides of the sheet material to form a tube.The second seal 38 (a tap seal) is formed in one of the ends of thetubular sheet material by engaging and flattening the opposed walls ofthe sheet material tube.

REFERENCES

-   10 Water permeable sheet material-   12 Sheet material tube-   20 Reel-   30 Plant growth pot or bag-   32 Tubular sheet material-   34 Growth medium-   36 Lap seal-   38 Seal-   100 Apparatus-   200 Storage container-   202 First storage chamber-   204 Second storage chamber-   205 Outlet-   206 Conveyor belt-   208 Growth medium feeding tube-   209 Perforation or slit-   210 Dosing chamber-   211 First open end-   212 Pneumatic/hydraulic cylinder-   213 Second open end-   220 Piston-   230 Stirrer paddle blade/head-   300 Folding means-   310 Upper unit-   320 Lower unit-   400 Suction chamber-   500 First sealing means-   610 Welding jaw/second sealing means-   620 Protrusion-   700 Cutting means-   800 Grabbing and pulling means-   810 Jaw-   820 Jaw

1. A process for line production of plant growth medium pots or bags(30) with a closed bottom end and an open top end comprising the stepsof: i) continuously folding the free end of a continuous length of waterand air permeable sheet material (10), preferably supplied on a reel(20), into a sheet material tube (12) around and beyond a free end of agrowth medium feeding tube (208); ii) forming a first sealing in thesheet material tube (12) by engaging and flattening the opposed walls ofthe sheet material tube (12) at a position beyond the free end of thegrowth medium feeding tube (208); characterized in that the methodfurther comprises the steps of: iii) through the free end of the growthmedium feeding tube (208), filling the sheet material tube (12) with ameasured amount of growth medium (34); iv) forming a second sealing inthe sheet material tube (12) by engaging and flattening the opposedwalls of the sheet material tube (12) at a position above the positionof the growth medium (34); v) separating the part of the sheet materialtube (12) positioned downstream from the second sealing to form a firstplant growth medium bag (30) with a closed end and an open top end; andoptionally vi) repeating the steps i), and iii)-v) several times to forma plurality of plant growth medium bags (30) with a closed end and anopen top end.
 2. The process according to claim 1, wherein thecontinuous length of water and air permeable sheet material (10) isadvanced by grabbing the first sealing in the sheet material tube (12)and pulling the first sealing further away from the free end of thegrowth medium feeding tube (208).
 3. The process according to claim 1,wherein step i) comprises sealing the overlapping sheet side parts toone another.
 4. The process according to claim 1, wherein the water andair permeable sheet material (10) comprises a) fibers coated with athermoplastic material and/or b) fibers of a thermoplastic material; andwherein the sealings are made by heating.
 5. The process according toclaim 1, wherein the growth medium feeding tube (208) is connected to agrowth medium delivering unit comprising: a storage container (204)adapted for holding growth medium, and with an outlet (205) in thebottom wall; a stirrer (230) configured to maintain the growth mediumhomogeneous in the storage container (204); and an open-ended dosingchamber (210) configured to move between a first position and a secondposition; wherein a first open end (211) connects to the outlet (205) ofthe storage container (204) in the first position, and wherein a secondopen end (213) connects to an inlet of the growth medium feeding tube(208) in the second position, while the first open end (211) disconnectsfrom outlet (205) of the storage container (204), thereby removing adosage of growth medium from the storage container (204), through theopen-ended dosing chamber (210), and into the growth medium feeding tube(208).
 6. A growth medium pot or bag (30) obtainable by the processaccording to claim
 1. 7. A growth medium pot or bag (30) with a closedbottom end and an open top end, the growth medium pot or bag comprisinga tubular sheet material (32) having two sides, and two ends, andsurrounding a portion of growth medium (34); wherein the tubular sheetmaterial (32) is made of a single sheet of water and air permeable sheetmaterial being sealed with two seals formed in said sheet material;wherein a first seal (36) of the two seals is a lap seal joining the twosides of the sheet material to form a tube; and wherein a second seal(38) of the two seals is formed in one of the ends of the tubular sheetmaterial (32) by engaging and flattening the opposed walls of the sheetmaterial tube.
 8. An apparatus (100) for use in the process according toclaim 1, the apparatus comprising: a storage container (200) adapted forholding growth medium, and comprising a growth medium feeding tube (208)with a free end; wherein the storage container (200) is adapted fordelivering dosages of growth medium through the growth medium feedingtube (208); folding means (300) adapted for continuously folding thefree end of a continuous length of water and air permeable sheetmaterial (10), preferably supplied on a reel (20), into a sheet materialtube (12) around the growth medium feeding tube (208); a suction chamber(400) adapted to be positioned around and beyond the free end of thegrowth medium feeding tube (208), and adapted to be in a) an open firstconfiguration and b) in a closed second configuration; wherein when inthe closed second configuration the suction chamber (400) encloses thefree end of the growth medium feeding tube (208) and the sheet materialtube formed around it, and engages and flattens the opposed walls of thesheet material tube at a predefined distance downstream from the freeend of the growth medium feeding tube (208); and subsequently removesair out of the suction chamber (400), such that a dosage of growthmedium in the storage container (200) is transported through the growthmedium feeding tube (208) and into the sheet material tube within saidsuction chamber (400); a first sealing means (500) adapted for forming asealing in the sheet material tube by engaging and flattening theopposed walls of the open end of the sheet material tube at a positiondownstream to the suction chamber (400); wherein the free end of thegrowth medium feeding tube (208) is configured with one or moreperforations or slits (209) extending through its walls; and cuttingmeans (700) adapted for separating a formed plant growth pot or bag (30)from the continuous length of water permeable sheet material (10) bycutting downstream from the sealing to form a plant growth pot or bag(30) with an open top end and a closed bottom end.
 9. The apparatus(100) according to claim 8, further comprising a second sealing means(610) adapted for lap sealing the sheet material tube.
 10. The apparatus(100) according to claim 9, wherein the second sealing means (610)comprises a welding jaw (610), and wherein a part of the free end of thegrowth medium feeding tube (208) comprises a protrusion (620) adaptedfor receiving said welding jaw (610).